Immunopathology of analfurunculosis in the dog

Perianal tissue obtained from 10 normal dogs and 40 dogs with anal furunculosis was immunostained in order to determine the number and distribution of B lymphocytes/plasma cells (expressing IgG, IgM or IgA) and T lymphocytes (expressing the CD3 marker) within the inflammatory infiltrates. Differences in these parameters between tissue obtained from affected German shepherd dogs (n = 20) and affected dogs of other breeds (n = 20) were recorded. The immunological phenotype of cells comprising lymphoid follicles and associated with ductal eosinophilic pustules observed in the anal sacs of dogs with anal furunculosis is described. The results of this study suggest that a simple immunological defect does not underlie the predisposition of dogs of the German shepherd breed for anal furunculosis.